Right side fans quit

[Shinny]

The right side cooling fan has quit in my '88 TR. Left hand side comes on and stays on when it should. Checked the fuse panel and there are no blown fuses. Swapped the left hand and right hand relays on the fuse panel and the right hand fan continues to stay off. There are no coolant leaks, the fluid level in the tank is correct, and the temperature at highway speeds is fine. I'm wondering if the right and left hand fans have their own temperature sensors and perhaps the sensor on the right has given up. I have looked at the schematic and it's unclear. Will do more digging tonight, but has anyone else out there found a common cause of this problem?

Thanks,
Dave

[Steve Magnusson]

Originally Posted by Shinny

...I'm wondering if the right and left hand fans have their own temperature sensors and perhaps the sensor on the right has given up...

No, just one sensor (thermoswitch) should activate both water fan relays.

Originally Posted by Shinny

...but has anyone else out there found a common cause of this problem?...

Many of us Most likely a "fried" terminal in the j white connector (you can't see the fault unless you unplug the connector -- and you'll have to unplug the k connector to get access to unplug the j connector). See this thread for description/photos:

Testarossa Airconconditioning

[Shinny]

Yup. Fried to a crisp. Both pin 2, right side, and pin 5, left side cooling fan. The K connector is fine. I looked around but did not find a replacement vendor for the white connectors, or the female mating lugs inside. Do you have a source? And btw, what is the trick for removing the lug ends from the plastic gang connector? I poked and prodded but could not get them to release.
Thanks again for the tip.

[Steve Magnusson]

Thanks for the feedback confirming the cause of your problem. (You might want to have a look at the fuel pump connections, too, to see if they are starting to suffer from the same disease).

Ricambi America caries both the female metal terminal and the white connector shells (not sure which one is "j" -- the 4 have different keying strip locations that makes each one unique):

white connector female terminal 12278744 with label.jpg

TR white connector 12284780.jpg

You're lucky if the male pins on the PCB and/or the PCB itself didn't take a beating too. If you do a search on "TR white connectors" you should get many threads from prior discussions -- most of us have either made alternate repairs to bypass the white connectors or sent the PCB to Dave Helms at Scuderia Rampante for his modifications/additions (which also bypass the commonly troublesome high current circuits) since another failure seems likely/unavoidable with the stock parts.

[302Tim]

Dave, to get you back on the road quickly you may get lucky by removing the pins as Steve describes above, lightly sanding the contact spots (pads) on the pins, and trying to re-bend them to where they make contact (or close) with each other again. Re-insert the pins in the white connectors (after bending the retaining tabs out again) and reinstall the connector in the fuse panel. This worked for me though absolutely should only be considered a temporary fix until more permanent repairs can be made. You can read all day in many threads here in the TR forum but I can save you some time with a few points:

1) As several of the high amp electrical motors/pumps wear, they require more power to operate. This increased demand draws more current through the circuit than originally designed and builds heat. The heat is concentrated at the fuse panel and connections, as you have discovered. The multi-layered fuse panel PCB can break down, the connectors melt, and the pads on the pins open up from the heat. The result is what you have now.
2) Primarily five affected circuits: LH and RH water fans, LH and RH fuel pumps, Air conditioning circuit. Some have reported issues with the oil fans as well but oil cooling typically does not need fans. I have a 40K mile car and my oil fan circuity is perfect whereas my other circuits melted.
3) Owners have replaced fuse panels (back when they were available), female pins and white connectors only to find the problem return. The root of the problem is in the individual circuits and the electrical components within them. Replacing the pins and connectors is a great cosmetic fix but likely only a short-term physical solution.
4) As Steve points out there are several avenues for a more permanent solution. Fixing sooner rather than later will save you a lot of heartache.

Best of luck, let us know how things work out.

[Mr.Chairman]

The big issue is that the fuse box right out of the box was at its limits.. The slightest increase in draw causes, plain overload and melt down. The white connectors is not going to fix anything, the issue will return sooner than later plus if you do not address the fuse box now the chances of the adjacent circuits getting effected raises.. These boxes are hard to find and you really need to take care of your existing box.. Send the box to Dave Helms at Scuderia Rampante, get the mod intall it and the issue is put to bed. A new fuse panel will not solve the problem either. The longer you wait the more damage can be done to the circuit boards in the fuse box.. I recommend all high draw circuits to be addressed.. I never did my oil cooling fans because in almost 5+ years of ownership in the dead heat of summer, my oil temp has never reached 210 degress (when oil fans kick on). The fuse box is the beginning of starting a solid foundation in the TR. Its a must.

R

[Shinny]

Thanks one and all for your recommendations. I yanked the remaining white connectors and am not yet in serious trouble with other circuits. Fuel pump connectors are a little bit brown, A/C is fine. I have just picked myself up off the floor after pricing a new fuse box at Ricambi. I had steeled myself for expensive, but not six grand plus. I have sent a PM to Dave Helms regarding an upgrade of mine, which I will probably do over the winter. In the meantime, I am going to cobble a direct connection to the male pins for the fans which should get me through the rest of Ferrari season, which is rather short in Canada. I am fortunate to live on Manitoulin Island, where we have no stop lights, no parking meters, and no train tracks. The TR will actually run quite fine here, thank you, with no fans working at all. But I get the inherent design flaws in the fuse box and will address them after the snow flies. Thanks again.

Dave

[Mr.Chairman]

Sir.. with all due respect.. Get your fuse box out of the car and Dave can turn it around for you in no time. Your quick fix has the potential of ruining your fuse board for good.. Be smart and all in all you can have this issue resolved in 7-10 days max.. Plenty of time to drive her and enjoy the summer..

R

[Shinny]

Thanks, Mr. Chairman, for your concern and advice. I will see how busy Dave is and take it from there.

Dave